A distributed ledger is a list of transactions that are not centrally stored. In cryptocurrency a distributed ledger is usually a blockchain and is shared on a peer to peer network (which we will call nodes) without any central control. For the distributed ledger system to work, all participants must have an exact replica of the ledger. This is achieved by the ledger software connecting to other nodes and ensuring their ledger is up to date with the latest transactions. Distributed ledger technology was a breakthrough in the field of digital currency as it allowed copies of transaction records to be held by anyone, due to the cryptography and backward tracing elements securing the ledger from alteration.
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